轴对称实体迴转杂交应力元

用杂交应力法导出一系列新的八节点、四边形轴对称实体迴转元,对每种元,边界二次位移插值函数相同,内部应力场各异,对两类不同选择假定应力场的方法进行了对比研究,以內压力作用下的厚壁筒及厚球为例,对各种应力场进行了数值比较,并选出了一种较好的元,该元给出了远较传统的八节点轴对称假定位移元准确的应力分布。

AXISYMMETRIC SOLID-OF-REVOLUTION ELEMENTS BASED ON THE ASSUMED-STRESS HYBRID MODEL

A series of axisymmetric solid-of-revolution elements with 8-node and quadrilateral cross section have been developed based on the assumed-stress hybrid model. A quadratic boundary displacement assumption is employed for each element and a variety of interior stress assumptions have been made. Two different kinds of method used for developing stress field have been studied. Example problems of a thick cylinder under internal pressure and a thick sphere under internal pressure are utilized to evaluate the various elements, and a desirable stress assumption has been identified. Comparions of present results with those obtained by the use of 8-node element based on the assumed displacement model indicate that this hybrid stress element is far superior in predicting the stress distribution.